Calithera Biosciences, Inc. (Nasdaq:CALA), a clinical stage biotechnology company focused on the development of novel cancer therapeutics, today announced that the U.S. Food and Drug Administration (FDA) has granted Fast Track designation to CB-839 in combination with cabozantinib for the treatment of patients with metastatic renal cell carcinoma who have received one or two prior lines of therapy, including at least one vascular endothelial growth factor tyrosine kinase inhibitor or the combination of nivolumab and ipilimumab. CB-839 is a first-in-class, oral, selective, potent inhibitor of glutaminase being evaluated in the CANTATA trial.
“Despite a number of new therapies for the treatment of renal cell carcinoma, there remains a significant unmet need among advanced patients who have received prior treatment,” said Susan Molineaux, PhD, President and Chief Executive Officer of Calithera. “We are pleased that CB-839 has been granted Fast Track designation, demonstrating the FDA’s commitment to facilitate the development and expedite the review of our glutaminase inhibitor as an important new therapy for patients with advanced or metastatic renal cell carcinoma who have failed prior systemic therapy.”
In preclinical studies, CB-839 has been shown to halt the growth of or kill cancer cells across a range of tumor types. The compound has demonstrated antitumor activity in several different tumor models in animals. In preclinical toxicology studies, CB-839 was well tolerated in animals at doses above those shown to inhibit tumor growth. CB-839 has also shown strong synergy with immunomodulatory agents and several kinase inhibitors that target growth factor pathways.
Inhibition of glutaminase also results in accumulation of glutamine in tumors. Glutamine, which is frequently depleted in the tumor microenvironment due to uptake by tumor cells, has been shown to be an important nutrient for T-cell growth. CB-839 could potentially have an impact on the treatment of cancer by first starving the tumor cell, and second facilitating the activation of T-cells in the nutrient-deprived tumor microenvironment.
